Tanking is the act of fitting a ship with modules in order to improve its defensive capabilities to resist, absorb, or mitigate incoming damage, thus preventing or delaying your ship's destruction.

Damage to your ship is represented by the Ship Status Panel - the three rings on the top of the status panel represent, from outermost to the inner ring, your ship's shield, armor and structure (also called "hull"). As you incur damage, each ring will fill with red coloring, starting with your shields, then your armor, and finally, your structure. When the structure ring is completely red, that means your hull has been breached, and your ship is destroyed - and you'll find yourself floating in space in a pod.

There are four principle components to tanking:

Maximizing hit points

Resisting incoming damage

Repairing or recharging damage taken

Avoiding damage altogether

Tanking Types

Common methods used to mitigate damage taken by your ship during a fight:

Armor Tanking: Focuses on maximizing strength and effectiveness of your armor to withstand and/or repair damage. This is the most common type of defense for ships with a greater number of low-slots, where most armor-related modules are fitted.

Shield Tanking: Focuses on maximizing your shields' ability to withstand and/or repair damage. This is the most common type of defense for ships with larger numbers of mid-slots, where most shield modules are fitted.

Hull Tanking: Focuses on reinforcing the structure of your ship to withstand and/or repair damage. Generally, hull tanking is not considered to be very viable, as hull repairers are relatively inefficient.

Spider Tanking: Focuses on a fleet tactic in which ships mount remote armor repair modules so they can repair each other.

Speed Tanking: Focuses on maximizing the velocity of your ship, in order to avoid damage. This approach can be effective for some extremely fast ships, though it requires a highly skilled pilot to execute.

Range Tanking: Focuses on engaging from a distance so that you are out of the range of enemy fire.

Cloak Tanking: Focuses on the use of a cloaking device to avoid being detected, targeted or engaged.

EW Tanking: Focuses on electronic warfare modules to make it difficult for enemies to inflict damage. This approach is generally difficult to execute without the support of other ships and is often used in combination with speed and/or range tanking.

The Key to Tanking

There are two ways to minimise your incoming damage - moving fast and being small. The smaller and faster you are, the less damage you take from all primary weapon systems (with a couple of exceptions, such as bombs, smartbombs or doomsday devices - these don't care how small or fast you are).

When you fit armor plates and armor rigs, this makes you slower and less agile.

When you fit shield extenders and shield rigs, this makes you bigger.

If you do both, you get slower and bigger - thus, you take a lot more damage.

To find out why you take less damage by being small and fast, have a look at the missile and gunnery classes - the equations these weapon systems use to determine how much damage you take depend in part on your velocity and your signature radius. See Gunnery 101.

How Armor and Shield Resistances Work

Resistance percentages are calculated in a way that many people find confusing. A module may list itself as having a 30% bonus to resistances -- but the only time you'll actually see a 30% increase in resistance when using it is if your current resistance is 0%.

The way the calculations work is that the percentage is applied to the remaining vulnerability. If things didn't work this way, you'd easily get resistances above 100%, and shooting you would cause armor to grow on your ship.

Resistances are easier to figure out if you think in damage vulnerability rather than damage resistance.

Example: let's say we're flying a Harbinger, and we want to buff up our explosive resistance. The Harbinger already has a built-in 20% explosive resistance, so we have a 80% vulnerability, and if we get hit by something that does 100 explosive damage, we take 80 damage. Pretty simple.

That's still a lot of damage, so we now fit an Armor Explosive Hardener I, which gives us a 50% resistance bonus (the game lists this as a -50% resistance bonus which is also confusing). This 50% is applied to the remaining vulnerability, which if you remember is currently 80%. Half of 80% is 40%, which means this is our new vulnerability, and thus a 60% explosive resistance. If we get hit by that explosive damage missile again that deals 100 damage, now we are taking only 40 damage.

(Now on slide 8) But we want to reduce this even more. So we fit an Energized Adaptive Nano Membrane II. This is a super awesome module that gives us an extra -20% resistance to all four damage types. However we now run into stacking penalties, which apply to armor and shield resistance modules and rigs. The second module (that is the module or rig with the second-biggest bonus) that affects a specific damage resistance is only 87% effective, the module with the third-biggest bonus is 57% effective, and it gets less and less effective as you fit more of the same thing. Because we now have two modules that affect explosive resistance, the smaller bonus (i.e. the -20% from the EANM) is actually only 87% effective, which means it only gives us a 17.4% bonus to armor resistance. Note that the other EM, thermal and kinetic resistances are unaffected because we only have one resistance bonus for each of them, so those three still give the full 20%.

Remember we had a vulnerability of 40% from the previous slide. This -17.4% is applied to this 40% vulnerability, which results in a 33% vulnerability, and a 67% explosive resistance. The missile hitting us for 100 damage now only deals 33 damage to us.

Because of stacking penalties, and the way resistances multiply together, it is not possible to be 100% resistant to a damage type. The best possible resistance is about 99.3% EM resistance, which is possible on a Loki with officer modules (link in chat: http://i.imgur.com/FHaNYk4.png - point out the use of 100% EM incoming damage) - if doomsday devices could be used on sub-capital ships, this Loki would survive three strikes.

Common Armor Tanking Ships

Because they generally have more low slots, and therefore can fit more armor-tanking modules, Gallente and Amarr ships are usually armor tanked. The Gallente Hyperion and Proteus, and the Amarr Abaddon and Legion, have the strongest sub-capital armor tanks in the game - and can exceed 60,000 hit points in armor protection, and over 200,000 effective hit points in total, with the right skills, modules and implants.

Many Minmatar ships can also be armor tanked, as they typically have a more balanced distribution of low, mid and high slots.

Very few Caldari ships armor tank, with the exception of the Scorpion and Blackbird. These are sometimes (and in the Scorpion's case, usually) armor-tanked so that they can keep as many midslots as possible free for ECM.

Armor Tanking Modules

Armor Plates

Armor plates are the simplest armor module; they add a flat amount of armor to a ship. These can be an excellent way of adding buffer to your tank, but the penalties of increased mass make them uncommon in PvE.

The large amount of mass they add to a ship, reduces agility, so are rarely used on faster ships.

While 1600mm plates are the largest size, they can often be fitted to cruisers, giving a big boost to their EHP.

Note: the Reinforced Rolled Tungsten plates are the Meta 4 version and are also very popular. They don't add as much armor HP than the T2 steel plates, but they use significantly less powergrid and add less mass (thus retaining some of your agility). They can be useful if you're short on PG.

Damage Control

A Damage Control module gives a significant boost to any ship's durability by giving resistance bonuses to armor, shields and hull. This is the only module to increase hull resistances, which makes it very valuable in most ships, as it gives you a larger buffer before your ship is destroyed, buying you more time to escape if necessary.

It is a passive module, but it is easy to fit and uses very little energy (less energy than the base cap recharge at 0% cap).

These resistance bonuses don't incur stacking penalties with other tanking modules but do with `Armor Resistance Shift Hardener`, only one Damage Control can be active in a ship at a time.

Extremely common in PvP, some snipers or EWAR might choose not to fit them but most will. Less common in PvE but can still be useful for armor tanking PvE.

If you fit only one tanking module to your ship, the DCU is the module to use.

Armor Hardeners

Armor Hardeners are active modules that boost one of the four armor resistances: EM, Thermal, Kinetic or Explosive.

Compared to membranes, they use capacitor (not much though) and slightly more CPU but offer a large boost in effectiveness

Realize that when you are in game the fitting window won't show you an active module's bonus until you actually activate it. Which means you have to either be in space or enter simulation mode. (Alt-F is the default shortcut combination to open your fitting window).

Reactive Armor Hardener

This is a new module introduced in Inferno and you can only fit one.

Uses more capacitor than standard armor hardeners, when you turn it on it gives you -15% extra armor resistance across the board to all resistances.

However it shifts its resistances according to incoming armor damage, moving the resistances gradually per cycle. Example: if you are being hit by only EM damage, the 15% to all resistances will gradually shift to 60% EM resistance and 0% all other resistances The shifting effect is only activated when your shield has gone and you are taking armor damage.

Shifts by 6% per damage type per cycle. If you're being continually hit by only EM damage, each cycle your EM resistance will increase by 18% and the other three resistance will each decrease by 6%.

Useful module for buffer tanking if you have a lot of armor EHP and will survive long enough for the shifting resistances to benefit you.

Also it doesn't suffer from normal stacking penalties with other armor modules but does conflict with the DCU.

The Armor Resistance Phasing skill will reduce cycle time and capacitor need of the module, which makes it a much better module. Before Kronos, the cap use reduction was less than the cycle time reduction meaning you would use more cap per time with higher skills. In Kronos both reductions go in step, so capusage stays constant.

The modules looks at damage *after* resistances and shifts resistances accordingly. This makes the module usefull even if you are receiving omni damage as it will try to plug your worst holes.

Energized Plating

These are armor membranes, passive modules that boost armor attributes. They take a lot of CPU, but only 1 powergrid

EANM (Adaptive) -- The Energized Adaptive Nano Membrane gives a boost to all 4 resistances. Very popular to increase armor resistance across the board. 30/36 CPU for T1/T2 versions.

EALM (Layering) -- this module gives your ship a percentage bonus to armor. If you'd like to fit an armor plate, or an additional armor plate, consider this module instead. Because it's a percentage bonus, you get more benefit on larger ships. The T2 version of this has the same effect as a T1 trimark armor pump rig - the rig might be a better, to keep your low slots free.

Specific hardeners (EM/Thermal/Kinetic/Explosive) -- these are used to boost one of the four resistances. Explosive hardeners are the most popular, because most ships have very low explosive resistances. In a ship with lots of tanking slots, you may do better to have these modules than multiple EANMs.

The EANM and the specific energized membranes become more effective when you train your EM/Explosive/Kinetic/Thermal Armor Compensation skills, gaining 5% increase with each level. For example, the T2 EANM gives you 20% to all resistances. If you train all the Armor Compensation skills to 4, this will become a +24% to all resistances.

The Imperial Navy Energized Adaptive Nano Membrane is one of the most popular faction modules and is pretty cheap nowadays.

Resistance Plating

These modules are very similar to the energized membranes above, except they use no CPU and are less effective.

They have the same versions as the energized membranes.

They are very useful if you're short of CPU, and the faction variants approach the effectiveness of the energized modules.

Use Energized Plating if you can, downgrading to Resistance Plating if you run out of CPU.

Armor Repairers

These modules repair your ship's armor, just as you'd expect. The better modules are more efficient, and may cycle somewhat faster.

Armor reppers are not usually recommended in fleet PvP, because they cycle fairly slowly. If your ship is called primary, it's likely that the repper won't have time to cycle before your ship explodes. Fitting a buffer tank, and warping out when you're targeted, is recommended instead.

Reppers are, however, very useful in PvE activities, since NPC ships don't typically deal damage as quickly. See also Armor Repairer. They can also be extremely effective in solo PvP.

For ships with armor repairer bonuses, such as the Gallente battlecruisers and battleships, two armor repairers can be very effective for mission runners, if cap stability can be maintained.

Ancillary Armor Repairers

Similar to the Armor Repairers with the following differences

Always uses the same cap as a normal (T1/T2/Named) Armor Repper.

Uses Nanite Repair Paste.

Small uses 1 paste per cycle.

Medium uses 4 paste per cycle.

Large uses 8 paste per cycle.

Holds 8 cycles worth of paste at a time.

Reload time is 1 minute.

When not loaded with Nanite Repair Paste, the AAR has 3/4 the rep amount as a T1 Armor Repairer.

When loaded with Nanite Repair Paste, the AAR triples the rep amount (repairs 2.25x a T2 repairer when loaded).

Remote Armor Repair Systems

Remote repair modules repair armor on other pilots' ships. Note that you must target the ship to be repaired, and that your cannot repair your own ship with a remote repper. They are more useful in fleet operations than regular reppers, for a couple of reasons. First, one repper can repair many ships, given time. Second, the repper cycles more quickly than an onboard repper does. Third, if several ships have them, they can focus their repair power on whatever ship in the fleet is being attacked, giving that ship a great deal of armor repair capability. This is known as Spider Tanking. The problem with using the remote repair modules on non logi ships is the range, all the ships need to remain in a small area.

Note that remote repair modules take a significant amount of capacitor to run -- non-logistics ships will probably need a cap booster module to use it for any length of time.

Armor Rigs

Trimark Armor Pump -- The Tech I version gives a 15% boost to total armor, at the cost of some ship speed. It's the rig equivalent of the Armor Layering Membrane. Trimark rigs are not stacking penalised (armor HP is never stacking penalised). They apply after any fixed HP bonus from armor plates. Incurs a 10% penalty to maximum speed.

There are also damage-specific resistance improvement rigs. The most commonly used is the Anti-Explosive Pump, since armor tanks are generally weakest to explosive damage. Armor resist rigs are stacking penalized with; Armor Hardners, Energized Planing and Resistance Plating modules. Armor resist rigs penalize speed by 10%.

Auxiliary Nano Pump -- Increases a ship's armor repairer repair amount per cycle by 15% at the expense of increased power grid use for local armor reps. Suffers from stacking penalties if you fit more than one.

Nanobot Accelerator -- This rig speeds up armor repair module cycle times by 15%, again at the cost of power grid use. In theory this is more effective for active armor tanks than the Auxiliary Nano Pump, but because it also causes you to use a lot more capacitor, it is used less often. Despite what the description says, it doesn't suffers from stacking penalties if you fit more than one.

Armor Tank Implants

There are several useful implants that focus on armor tank improvement, all from the Inherent Implants "Noble" series:

This is a series of implants that fit into slots 1-6. Each provides a bonus to armor hit points, but when you fit the entire set, it provides a multiplicative total bonus of 53.63%. Unfortunately, a complete Slave set cost about 1.8 billion ISK or more.

There is a less expensive low-grade Slave set, which provides an aggregate bonus of 33.83% to armor hit points. These are a relative bargain at only 750 million ISK or so.

You can mix & match HG and LG Slave implants, for a final armor HP bonus partway in between.

You can also get some officer-fit implants, that are variations of existing implant series except more effective. Once example is Akemon's Modified 'Noble' ZET5000 implant, which is an 8% version of the Hull Upgrades HP-10xx series of implants. It's correspondingly more expensive as well.

Armor Tanking Strategies

Armor tanking emphasizes the use of the low slot modules described in the previous section to increase armor hit points, resistance to damage and repair damage done to it. Regardless of the approach taken to armor tanking, it is wise to understand that armor has an inherent weakness to explosive damage and plan your resistance modules accordingly.

There are two primary approaches to Armor tanking:

Buffer tanking

Active tanking

Note:Passive tanking doesn't exist in the same sense as in shield tanking, since armor doesn't repair itself.

Buffer tanking

Typically used for PvP, the buffer tank is based around the principle of having high damage resistance and as many hit points as possible, thus increasing the Effective HitPoints (EHP) of the ship. The concept behind this is simple, add enough EHP to your ship to outlast your opponent through the use of active and/or passive resistance modules, which complement the Armor Plate modules that add raw hit points.

Ideally this should free up enough fitting slots, CPU and power grid to fit bigger weapons and more combat utility modules, such as tackling equipment, to maximize your damage output. This type of fitting uses a minimal amount of capacitor to run Armor Hardeners making it easily sustainable, but can be made fully passive by using only passive resistance modules instead. The primary drawback to Buffer Tanking is that you have no way to repair yourself, so when you run out of hit points you are toast.

Most common in fleet PvP, but also group PvE (like incursions, wormhole anomalies / signatures and a few others). In PvP a fleet will overwhelm an active tank in fairly short order, whereas a buffer tank will give you more survival time. Although, some ships with faction gear and active tank bonuses can field some extremely resistant active tanks that can take on more than you might think. In general if you are expecting to have Logistical support (friends to rep your armor) then you want to buffer tank more towards resistance, because the higher your resistances the more effective logistic reps are. While if you don't expect logistical support you only care about the Effective Hit Points, so whatever combination gives you more effective hit points is the best option.

Active Tanking

Active tanking is most commonly used for solo activities such as mission/complex running, ratting, and solo PvP. Active Tanking differs from Buffer Tanking in that it uses Armor Repair modules to actively repair damage done to the ship. You should be careful to include enough resistance and buffer to keep your repair modules from being overwhelmed by incoming damage; frequently this means packing resistance modules (either passive or active) that compensate for the specific types of damage you expect to be receiving.

This type of fitting takes a lot of capacitor to sustain your cap-hungry Armor Repair modules so it should ideally include modules such as Cap Rechargers and/or Capacitor Batteries to balance out and maintain capacitor stability.

Capacitor stability is important because it allows you to leave your Tank modules turned on without ever worrying about running out of capacitor. So long as incoming damage is less than what your repair modules can handle your ship should be able to sustain that level of damage indefinitely. This is commonly referred to as Perma-tanking. If incoming damage exceeds your repair capacity you will gradually run out of Hit Points and die. This is commonly referred to as having a broken tank.

For PvP purposes a Cap Booster can be used to temporarily supplement capacitor output to allow for short bursts of heavy tanking. The primary drawback to this approach is that unlike the capacitor stable fitting described above, when you run out of charges to run your Capacitor Booster, you quickly run out of capacitor, your tank will fail and you will die horribly.

Similarly, weapon systems that drain your ship's capacitor will effectively disable your active tanking modules. As above, your tank will fail and you will die horribly. In this case, the Capacitor Booster can be used on an otherwise capacitor stable fitting to provide emergency power to prevent being drained and destroyed.

Spider Tanking (Armor)

In simple terms, Spider tanking involves the use of a Buffer and/or highly resistant tank that is repaired remotely by other ships in your squad who are in turn repaired by remote repair modules on your ship. This is an advanced technique that requires a good deal of coordination to function effectively, and will be covered later in this guide.

Fitting Strategy

Whether fitting active or buffer tanking it is advisable to use some sort of fitting tool, such as EFT or Pyfa, to create and compare fits:

For PvP, fit the largest single plate you can, and then play around with Armor Hardeners, Energized Plating, Resistance Plating to get the most Effective Hit Points that you can get.

For PvE, fit one or two repair modules (depending on how much cap you have available), and then fit as many armor damage resistance modules of the appropriate damage types for the expected enemy.

The primary armor tanking skill is Hull Upgrades, which grants a 5% bonus to armor hit points per skill level. Hull Upgrades V is the prerequisite for the most useful Tech II armor resistance modules.

Mechanics is also required to fit armor repairers, and should be trained up to level V to fit Tech II equipment and operate it effectively. Mechanics also provides a 5% bonus to structure hit points per skill level.

Training the four armor-compensation skills is also important, since most of the commonly-used armor hardener modules will benefit significantly from them. These skills increase resistance to specific types of damage by 5% per skill level for passive armor hardeners, before Retribution 1.1 these skills also helped active modules but this is no longer the case. For regular armor tankers, each of these skills should be trained to at least level III or higher, IV is highly recommended. Maybe even V once your ships get bigger and more expensive.

Repair Systems is required to operate armor repair-units effectively - each level reduces repair systems duration by 5%. Tech II units are available at skill level IV, though training to level V is recommended to minimize the length of repair unit cycles. It should be noted that a reduction in activation time increase the capacitor need of the module.

Armor Layering reduces the mass penalty of fitting armor plates by 5% per level. Which means that if a ship is fitted with an armor plate, training this skill up improves both the ships agility all the time, and top speed when using an afterburner or microwarpdrive. In other words training this skill up will reduce some of the disadvantages of choosing to armor tank.

Armor Resistance Phasing is useful if you fit a Reactive Armor Hardener, It reduces the cycle time of the module (10% per level) and decreases the capacitor need (10% per level). More information on the Reactive Armor Hardener later in the class.

Shield Management while not technically an armor tanking skill, increases your overall shield hit points by 5% per level, which helps any ship, regardless of the way its tanked.

Tactical Shield Manipulation also not technically an armor tanking skill (actually required for a Tech 2 shield tank) but it helps increase your shield buffer. When your shields fall below 25% damage starts "leaking" through to your armor, training this skill helps minimize how much damage leaks through, when trained to level 5 no damage leaks through. This is a "nice to have" when it comes to armor tanking but not required.

Armor Module Reference

(Ranges are for tech1 – tech2 versions)

Module Type

Fitting

Bonuses

Notes

Cap

PG

CPU

Resist

Armor

Damage Control

1

25-30

10-15%

Also adds 7.5-12.5% shield and 50-60% structure resists

Armor plates

100-

8-18

5-30

263-1050

800-

23-28

200-500

2100-4200

Resistance plating

Adaptive

1

8-15%

Regenerative

1

6-8%

Specific

1

20-26%

Damage-type specific

Energized plating

Adaptive (EANM)

1

30-36

15-20%

Regenerative

1

25-30

13%-15%

Specific

1

25-30

33-38%

Damage-type specific

Armor hardeners

Specific

30cap/20sec

1

33-36

50-55%

Damage-type specific, can be overloaded for 20% more resist

Armor repairers

Small

40cap/6sec

5-6

5-6

+60-80

Repairers can be overloaded for 10% more repair and 15% increased speed

Medium

160cap/12sec

150-173

25-28

+240-320

Large

400cap/15sec

2000-2300

50-55

+600-800

Remote Reppers

Small

59-54cap/5-4.5sec

7-8

20-24

+80-96

While the T2 versions use less cap per activation, the shorter cycle time means they still use more cap overall.

The Gallente and Amarr design ships which are mostly armor tanked. There are a few exceptions, and also a few ships which can mount shield buffer tanks for PvP.

A few Gallente ships can be well shield tanked, such as the Myrmidon and the Ishtar which often use passive shield tanks in PvE. Some Gallente ships, such as the Brutix can fit viable shield buffer tanks for PvP.

Amarr ships are almost all better suited for armor tanks, but the Arbitrator, Curse and Harbinger can mount good PvP buffer shield tanks.

Shield Tanking Modules

Shield Extenders

Shield Extenders are a mid slot mod are pretty straightforward -- they add base shield points. Remember that as increasing shield capacity also effectively increases shield recharge rate, they are also useful on passively tanked shields. As a drawback they increase the ship's signature radius which makes you faster to target and somewhat easier to hit with bigger weapons and for more damage. They also use significant power grid to fit. You can easily oversize these modules; try fitting medium shield extenders to frigates and large ones to cruisers or battlecruisers.

Damage Control

A Damage Control module gives a significant boost to any ship's durability by giving resistance bonuses to armor, shields and hull. This is the only module to increase hull resistances, which makes it very valuable in any tank. It is an passive module that is relatively easy to fit. These resistance bonuses don't incur stacking penalties with other shield tanking modules, making it very effective when combined with other hardeners and resistance amplifiers. If you fit only one tanking module to your PvP ship, the DC is the module to use.

Shield Hardeners

Shield Hardeners require varying amounts of CPU and only one MW of power grid to fit, but do almost nothing to improve resistances when they are not activated. Like all active modules they will not run when you don't have enough energy in your capacitor to run them, or when you cannot activate them (such as when docked or cloaked).

Adaptive Invulnerability Field

Among the Shield Hardeners, but worth mentioning separately, is the Adaptive Invulnerability Field which grants a bonus to resistance of all four damage types with one module. Although it requires more capacitor and more CPU to fit than the damage specific hardeners, it is still a very useful module.

Resistance Amplifiers

There are four damage-type specific resistance amplifiers -- these are used to boost one of the 4 resistances. They use no capacitor and require less CPU than active shield hardeners, and can thus be quite useful.

The Basic modules use less CPU than the normal variants and no power grid, but are much less effective. They are useful if you're unable to fit a standard Resistance Amplifier.

Shield Dampening Amplifiers have two varieties: those that require more CPU and one Power Grid and have higher resistances, and those that have lower CPU requirements and no Power Grid and provide lower resistances.

The EM/Thermal/Kinetic/Explosive Shield Compensation skills will increase the benefit gained from these passive amplifiers.

Shield Power Relays

Shield Power Relays are low-slot modules, and they trade away capacitor recharge rate, for an increase in the shield recharge rate – or more regained shield HP/sec. Note that they are exclusively used in an extensive Passive Shield tank, and even then on ships which have the many slots required. The reason for this is the hampered capacitor: this slows Shield Booster use, as well as to some extent, the longevity of active Shield Hardeners.

This module defines a passive shield tank. Since the relay modules fit in low slots, this means more Extenders may be fitted alongside them. On the other hand, this also means no low slot weapon upgrade modules for high damage. This will limit the situations where a passive tank may be used (see section on shield tanking strategy).

Shield Flux Coils

Shield Flux Coils are low-slot modules which trade the maximum shield capacity for an increase in the shield recharge rate. However, the reduction in capacity is minor, because of a paradoxical effect between maximum capacity and the regained HP/sec. This offsets the module's usefulness significantly. There are rarely situations where damage is so low that this module's tiny increase of HP/s is more useful, as compared to extra buffer HP (which indirectly increases shield recharge also) without the flux coil. They fit in a low-slot, but are outclassed by the more common Shield Power Relay. Thus, neither module competes with the slots for resistance modules and shield extenders.

Shield Rechargers

Shield Recharger modules are mid-slot modules which provide a modest increase to the shield recharge rate.

Shield Boosters

These modules repair, or boost, your ship's shield amount. The better modules are more efficient, and may cycle somewhat faster. Shield boosters are not very efficient, giving somewhere near 1 shield for 1 unit of capacitor for the meta 0 version and 1.5 shield for 1 unit of capacitor for the tech 2 version.

Unlike Armor Repairers, Shield Boosters give the boost at the beginning of the cycle time instead of at the end, meaning you can wait until you need the shields to activate the shield booster instead of activating it in anticipation of needing it, as is commonly done with armor repairers.

Shield boosters are not usually recommended on Uni fleet operations, because while they typically cycle fairly quickly, they do not give large boosts to shields for each cycle and they are hard on your capacitor. If your ship is called primary, it's likely that the booster won't keep up with the incoming damage. Similarly, passive tanks that emphasize shield recharge rate likely won't keep up with the incoming damage. Fitting shield hardeners or resistance amplifiers with shield extenders and being prepared to warp out if you take fire is the recommended strategy.

Shield boosters can be useful in PvE activities. Typically you can reduce the incoming damage by eliminating some of the NPC ships to slow the incoming damage. This combined with pulsing the shield booster on and off (or setting Auto-Repeat to off) and/or using a capacitor booster and other capacitor modules can help pilots establish a balance point between the incoming damage and the capacitor energy used to run the shield booster. This is an active strategy and does require more focus than a passive tanking PvE strategy but can bring other benefits in fitting.

Shield Boost Amplifiers

These modules improve the efficiency of Shield Boosters. Given that they occupy a valuable mid-slot, they are infrequently seen on cruiser sized and smaller hulls, but are more commonly seen on battlecruisers and battleships in PvE activities. These modules have a stacking penalty and typically no more than two is ever appropriate on any ship. Tech II gives 36% increase compared to a 30% for tech I. Note that they will boost the Ancillary Shield Booster as well.

Ancillary Shield Boosters

The Ancillary Shield Booster works in the same way as a normal Shield Booster does: it transfers capacitor energy into shield hit-points (HP), but it repairs a lot more shield HP per cycle than a normal Shield Booster does. It has an efficiency of around 1 shield unit to 1 capacitor unit, and this means it would use a huge amount of capacitor per cycle. However, the main advantage of the Ancillary Shield Booster is that it is able to use Cap Booster Charges as a direct source of cap energy. The size of the charge depends on the size of Shield Booster. It always uses 1 charge per cycle, and when the cap booster charges are spent, only then does it use the ship's capacitor. The maximum number of charges an Ancillary Shield Booster can hold is 10. The recharge amount doesn't depend on the charge size, so always load the smallest possible charges to give the largest number of cycles per reload. Due to the short cycle time the Ancillary Shield Booster depletes within 20 to 40 seconds depending on the module size. After the charges are depleted you can run the Ancillary Shield Booster without charges (it then uses your ship's capacitor) or you can reload it. But here is the biggest drawback of the module, the reloading time is 60 seconds. Currently only a tech 1 version is available. The quick transfer of cap energy to shield HP has made this popular in PVP.

The Ancillary Shield Booster's main features:

It works like a Shield Booster

It repairs more shield HP than a Shield Booster per cycle (around 1:2.2)

It needs high amounts of capacitor if you run out of cap booster charges (around 1:1)

It can use Cap Boosters as charges and uses one charge per cycle

Its reload time is 60 seconds

Remote Shield Boosters

Remote Shield Boosters operate similarly to local Shield Boosters by converting capacitor energy into shields, except in this case the shields are added to your target (ships, drones, anchored structures, etc). Note that you must target lock the ship to be repaired, and that your cannot repair your own ship with a remote shield booster.

They can be more useful in fleet operations than shield booster, for a couple of reasons. First, one RSB can repair many ships. Second, an RSB is generally more efficient than a shield booster. Third, if several ships have them, they can focus their repair power on whatever ship in the fleet is being attacked, giving that ship a great deal of shield repair capability. This tactic is used by Logistics cruisers and several T1 cruisers to try and repair the damage being done to friendly ships; thus the ship is either saved, or at worst survives a while longer, allowing the rest of the fleet some more time to burn through the hostile ships.

Remote repair is also the favoured form of defense in Incursions; ships will mount a large buffer tank to be repaired by a small number of highly skilled Logistics pilots.

Note that remote repair modules take a significant amount of capacitor to run -- your ship will probably need a cap booster module to use it for any length of time.

Power Diagnostics Systems

Power Diagnostics Systems are low-slot modules that increase your shield points, capacitor points and power grid while also reducing the recharge time of both shield and capacitor by a small percentage. They are not shield modules, strictly speaking, and can be found in the Engineering equipment section.

Capacitor Power Relays

These are not a shield tanking module, but I mention them because they have an adverse effect on shield tanking. Capacitor Power Relays are a low slot module that greatly increases capacitor recharge, which would be an active shield tanker's dream, except that to balance this capacitor power relays apply a penalty to shield boost amount when fitted. As such, they are not recommended for active shield tank fits. Capacitor Power Relays do not penalise passive shield tanks, and the penalty does not apply to Remote Shield Boosters.

Shield Rigs

For shield rigs, Jury Rigging III and Shield Rigging I are required to fit T1 rigs, though not to use them. All shield rigs bring with them the penalty of an increase signature radius on the ship using them.

There are several commonly used shield rigs.

Core Defense Field Extender works similarly to a Shield Extender by increasing shield capacity.

Core Defense Field Purger works similarly to a Shield Recharger by increasing the shield recharge rate. It is however, a lot more effective than a Shield Recharger, and is a staple on almost all passively-tanked ships.

Screen Reinforcers increases a ship resistance to single type of damage. The most commonly used is the Anti-EM Screen Reinforcer I, because typically shields are vulnerable to EM damage.

Anti-EM Screen Reinforcer

Anti-Explosive Screen Reinforcer

Anti-Kinetic Screen Reinforcer

Anti-Thermal Screen Reinforcer

Core Defense Capacitor Safeguard makes a shield booster run more efficiently reducing the cap requirement, whilst the Core Defense Operational Solidifier makes the booster run faster, increasing tank but also capacitor use. Unlike its armour equivalent, usually ignored in favour of a boost amplifier module.

Core Defense Charge Economizer reduces the powergrid need of shield extenders. Rarely used except in some very large buffers to pvp fits. Much cheaper than the general PG upgrade rig.

Other rigs

For Active shield fits capacitor will be a major concern and many will rely on a Capacitor Control Circuit I to make the tank work.

Shield Implants

There are various shield implants available on the market. These can be interesting for various shield fits. This is especially true for passive tanks, where the tank can be increased by 6% for just a few million.

You can also pick up the 'Crystal' pirate implant set for a large amount of ISK. This is a set of 6 implants that fit in slots 1 to 6, and taken together will increase your shield boosting rates to fantastic levels - such as this Sleipnir (link in chat: http://i.imgur.com/hwsM51F.jpg) which tanks nearly 1900 DPS of incoming damage, and that's without overheating or using a booster. The 'Crystal' set comes in high-grade, mid-grade, and low-grade versions, low-grade being for the poor people out there that can't afford the real deal. You can mix and match from different grade sets for a final boost bonus somewhere in between the two values stated on the presentation. (See here for boost percentages.)

Boosters

The "Blue Pill" range of boosters adds bonuses to the repair amount of shield boosters.

"Mindflood" boosters can also come in handy, as they increase capacitor capacity, which in turn boosts cap recharge rate and allows shield boosters and active shield hardeners to run longer.

Shield tanking Strategies

Shield tanking comes in three types.

Active shield tanks

Buffer shield tanks use shield extenders and resistance modules (like the Adaptive Invulnerability Field, and damage control) to maximize the ship's EHP (Effective Hit Points) without concern for recharge. This type of shield tanking is often used in PvP fleet fits.

Passive shield tanks

Active Tanking

Active tanking is most commonly used for solo activities such as mission/complex running, ratting, and solo PvP. Active Shield tanking differs from Passive Shield tanking in that it uses active Resistance and Shield Booster modules to actively repair damage done to the ship.
You should be careful to include enough resistance and buffer to keep your Booster modules from being overwhelmed by incoming damage; frequently this means packing resistance modules (either passive or active) that compensate for the specific types of damage you expect to be receiving.

This type of fitting takes a lot of capacitor to sustain your capacitor hungry Shield Hardener and Booster modules so it should ideally include modules such as Cap Rechargers to balance out and maintain capacitor stability. Unlike the Passive Shield tank Shield Power Relays are not recommended because they cripple your capacitor recharge rate making capacitor stability difficult to achieve. Shield Flux Coils still suck for the same reasons mentioned previously.

Active Tanking uses energy from the ship's capacitor to run a Shield Booster module which repairs damage to shields. Active shield tanks are stronger against higher bursts of damage but tend to drain the pilot's capacitor over time resulting in the tank 'breaking' during long engagements and are vulnerable to capacitor warfare (tactics which drain a ship's capacitor actively, such as Nosferatu and Energy Neutralizers, see the Capacitor Warfare Guide).

Capacitor stability is important because it allows you to leave your Tank modules turned on without ever worrying about running out of capacitor. So long as incoming damage is less than what your shield booster modules and passive recharge rate can handle your ship should be able to sustain that level of damage indefinitely. This is commonly referred to as Perma-tanking. If incoming damage exceeds your recharge capacity you will gradually run out of Hit Points and die. This is commonly referred to as having a broken tank.

For PvP purposes a Capacitor Booster can be used to temporarily supplement capacitor output to allow for short bursts of heavy tanking. The primary drawback to this approach is that unlike the capacitor stable fitting described above, when you run out of charges to run your Capacitor Booster, you quickly run out of capacitor, your tank will fail and you will die horribly.

Similarly, weapon systems that drain your ship's capacitor will effectively disable your active tanking modules. As above, your tank will fail and you will die horribly. In this case, the Capacitor Booster can be used on an otherwise capacitor stable fitting to provide emergency power to prevent being drained and destroyed.

Here is an example of a Minmatar Stabber cruiser fitted with an active shield tank.

Buffer Tanking

Typically used for PvP, the buffer tank is based around the principle of having high damage resistance and as many hit points as possible, thus increasing the Effective HitPoints (EHP) of the ship. The concept behind this is simple, add enough EHP to your ship to outlast your opponent through the use of active and/or passive resistance modules, which complement the Armor Plate modules that add raw hit points.

Buffer Tanks use shield extenders and resistance modules (like the Adaptive Invulnerability Field, and damage control) to maximize the ship's EHP (Effective Hit Points) without concern for recharge. This type of shield tanking is often used in PvP fleet fits.

Passive Shield Tanking

Unlike Armor hit points, shields will recharge themselves after taking damage. The Passive Shield tank is designed to maximize this natural recharge rate without the use of active Shield Booster modules. The concept behind the Passive Shield Tank is deceptively simple: find a ship with a relatively high natural recharge rate (Shield HP / Recharge time = Recharge rate), then add as many additional shield hit points to your ship as possible using shield extenders. Because the recharge time for a given ship is a fixed amount no matter how many points of shields you have, adding multiple shield extenders not only adds a lot of buffer, it indirectly increases the recharge rate because more Hit Points are being recharged in the same amount of time. Now add passive modules that increase the recharge rate even further, such as Shield Rechargers, Shield Power Relays and Power Diagnostic Systems; and you have a monster sized Buffer tank that regenerates very quickly without using any capacitor making your defense invulnerable to weapons that drain the capacitor. Shield Flux Coils also increase recharge rate, but should be avoided because they also lower your shield hit points, which is self defeating for the same reason adding Shield Extenders improves your recharge rate.

As the name implies, a fully passive tank does not require any modules that need to be “turned on” to function, and therefore does not require capacitor. The drawback to Passive Shield tanking is the number of modules required to pull it off, which leaves very little room to fit other useful modules such as damage improvement and tackling equipment, which makes this fitting of limited use outside of mission running and bait ships.

Passive Shield Tank relies on the fact that shields will naturally recharge themselves over time. This is achieved by increasing the resistance to various damage types, increasing the natural recharge rate (by adding recharge rate bonuses), and increasing the overall size of the shield (because recharge rate is proportional to shield capacity).

Note: This fitting is more about raw hit points than it is damage resistance, but if you have enough fitting room, Shield resistance amplifiers can be added to provide a little damage reduction. Some people use Adaptive Invulnerability Fields and Shield Hardeners to improve damage resistance, but these are active modules that require capacitor, thus making your Passive Shield tank not quite passive any more. This can be problematic because the Shield Power Relays you depend on to increase your shield recharge rate also totally gimp your capacitor recharge rate. For this reason careful balancing is necessary to make the Passive Shield Tank effective. When done correctly, however, Passive Shield tanking can be used to handle tough missions with a single ship.

Understand Shield Recharge Rate

It is valuable to understand the mechanics for shield recharge rate before you continue. All ships have some shields, and all shields have a recharge rate so this concept applies to every ship shuttle and pod in Eve, and thus to every pilot who undocks, and is similar to the recharge rate of a ship's energy capacitor. In fact it is the same as your capacitor's recharge rate.

In a ship's information screen, on the attributes tab, under the shield heading, is listed the total shield amount of the hull, and the shield recharge time. The recharge time expresses how long it will take to go from 0% shields to roughly 98% shields when the ship is sitting idle in space and no one is repairing the shields or damaging them. That last ~2% of your shields will take much longer.

But shields do not recharge at a constant (linear) rate. Imagine a ship with a 440 shield and a shield recharge time of 440 seconds. To find out how many shield points you regain per second you might divide: 440 shields / 440 seconds = 1.0 shields per second.

That is close but not quite correct. The average shield recharge rate is going to be 1.0 shields per second but sometimes it will be higher, and sometimes it will be lower.

The actual behavior is that when the shield is near 0% or 100% it replenishes slower. The peak recharge rate will be approximately 2.5 shields per second and will occur when the shields are damaged to somewhere near 25% of shield capacity remaining. Page 10 of the presentation shows this behaviour graphically.

This imaginary shield tanked ship above takes a constant damage of 5 damage every 8 seconds It will
slowly lose shields as the incoming damage is greater than the amount of shields recharging. Somewhere
around 50% shield capacity the shields will start to heal about 5 damage every 8 seconds and the tank
will stabilize at this equilibrium.
...
When a new damage source is then added to the scenario, adding an additional 5 damage every 8 seconds
the ship will begin to lose shields again. Somewhere around 35% the incoming damage will barely be
more than the ship replenishes and the shield tank will be broken as the ship falls below it's
peak recharge rate. From here the ship's recharge rate drops off quickly and the shields will be
exhausted soon.
...
If the original damage source is removed just as the ship is at 30% shields, leaving only 5 damage
every 8 seconds the shields might stabilize again but if the original damage source is removed as
the ship reaches 10% shields the recharge rate will be too low and the ship will continue to lose
shields, and continue into armor and hull damage unless the incoming damage is effectively reduced
to zero.

Shield recharge rates above ~98% shield is extremely low. For ships with small shield capacity it is essentially non-existant.

As we increase the total shield capacity, the average shield recharge rate will increase

The ship before with 440 shields and a 440 second recharge period is improved to have twice the shield
capacity: 880 shields and a 440 second recharge. The average shield recharge rate will be
880 / 440 = 2.0 shields per second, and peak recharge will be near 3.8 shields per second.

Similarly improving the shield recharge rate will increase the average shield recharge rate

We double the shield recharge rate instead: 440 shields in 220 seconds. Now
the average shield recharge rate will be 440 / 220 = 2.0 shields per second. Peak recharge increases
as well.

Passive Shield Tanking is a difficult concept and a separate wiki page,Passive Shield Tank, is devoted to fits and utilizing it in combat.

Spider Tanking (Shield)

In simple terms, Spider tanking involves the use of a Buffer and/or highly resistant tank that is repaired remotely by other ships in your squad who are in turn repaired by shield transporter modules on your ship. However, this is an advanced technique that requires a good deal of coordination to function effectively, and is better left for discussion later in this guide.

Fitting Strategy

It's often more sensible to increase the resistances of your ship than to increase the total number of shield points. The damage reduction of resistance modules is a constant where as the shield buffer reduces with each attack. The fitting requirements for resistance modules are often less than the fitting requirements for Shield Extenders. The one drawback is stacking penalties these will inhibit the effectiveness of additional resistance modules but do not apply to Shield Extenders.

Imagine you have a shield booster that repairs 100 points per cycle. If someone
deals you 1000 points of EM damage, to which you have a 10% resistance, will result
in 900 points of shield damage. Your shield booster will repair this in 9 cycles.
If someone deals you 1000 points of explosive damage to which you have 70%
resistance, you'll only sustain 300 points of shield damage, which the shield
booster will fix in three cycles.
So you would use three times as much energy, and take three times as long to repair
the EM damage because of the lack of resistance.

It is generally advised NOT to mix modules that increase shield recharge rate with modules that repair shield damage.

There are seven primary shield tanking skills, and four additional shield specific skills.

Shield Operation is the only Rank 1 skill in the set. It improves the natural shield recharge rate and also grants the ability to use Shield Booster modules. Tech 2 units are available between skill level III and V, depending on size.

Shield Management is a companion skill to Shield Operation. It improves a ship's maximum shield amount and also grants the ability to use Shield Boost Amplifiers, which magnify the size of shield repair amount for running Shield Boosters.

Shield Upgrades grants access to modules that increase a ship's maximum shield amount as well as passive shield hardeners and Shield Rechargers, a module that improves the natural recharge rate of shields, while also making it easier to fit all of these modules by reducing the Power Grid requirement to fit them.

Tactical Shield Manipulation stops damage from bleeding through low shields into armor. More importantly it is the prerequisite for Adaptive Invulnerability Fields, the most useful shield resistance modules. The skill requires Power Grid Management III and unlocks Tech 2 Adaptive Invulnerability Fields at level IV.

Shield Emission Systems grants the ability to use remote shield repair modules. Tech 2 units are available between skill level III and IV, depending on size.

Shield Rigging allows fitting of rigs that can increase total shields, shield resistances, passive shield recharge rates, and active shield booster cycle rates. Higher levels of the skill allows use of tech 2 rigs and also reduces the signature radius penalty that those rigs incur. You'll also need the basic skill Jury Rigging to fit rigs.

Training the four damage type-specific shield compensation skills is less important. The passive Shield Amplifier modules benefit most from them, but are not widely used, but active resistance modules (like Adaptive Invulnerability Fields) get no benefit at all. These skills are:

Other Skills

Energy Grid Upgrades provides access to modules that increase shield recharge rate as well as modules that influence the operation of the ship's capacitor. Power Diagnostic Systems, for example, are low slot modules that provide small increases to shield hit points, shield recharge rate, total capacitor capacity, capacitor recharge rate, and to powergrid available for fitting.